George Ruhe for The New York Times

“Yes, where are you sir?” the veteran Connecticut state trooper on the other end of the emergency call responded.

“I’m in the building,” Mr. Thornton said. “Uh, you probably want to know the reason why I shot this place up. This place here is a racist place.”

Seconds later, he added, “I wish I could have gotten more of the people.”

Throughout much of the call, which lasted 4 minutes 11 seconds, the voice of Mr. Thornton, a 34-year-old beer truck driver, was calm but tinged with exhaustion. He seemed eager to explain his bloody rampage, but unwilling to surrender. Having carried out the state’s deadliest attack in recent history on Tuesday at the Hartford Distributors beer warehouse in Manchester, Conn., Mr. Thornton delivered what amounted to a spoken suicide note.

The chilling call, made from somewhere inside the giant warehouse as people lay bleeding and dying and as officers from a half-dozen agencies swarmed the building, provides the first authentic glimpse into Mr. Thornton’s thinking, in his own words.

Mr. Thornton talked about his anger at his bosses and co-workers. He assured the trooper on the phone, more than once, that he was finished killing his colleagues, although he also expressed pleasure at his choice of handguns — “two of my favorites.”

He hinted broadly that he would kill himself before the police found where he was hiding — “When they find me, that’s when everything will be over.” He parried the trooper’s efforts to keep him on the line and finally told him, “Tell my people I love them.”

The recording, first posted Thursday on the Web site of The Hartford Courant, emerged as Mr. Thornton’s girlfriend and family members have maintained that racial harassment at the workplace pushed him over the edge, charges that officials with the company and the local Teamsters union that represented him have steadfastly denied.

Mr. Thornton had been called into a disciplinary hearing the morning of the shootings and was offered a choice of resigning or being fired, after officials accused him of stealing beer along his delivery route. Moments later, he opened fire.

Sometime shortly after 8 a.m., the trooper took the call, and in his own calm tone tried to keep Mr. Thornton on the line. He sympathized with his anger, tried to determine how much firepower the arriving SWAT team might face and repeatedly sought to get him to disclose his exact location.

“They treat me bad over here, they treat all the black employees bad over here,” Mr. Thornton continued in the opening seconds of the conversation. “So I had to take it into my own hands and handle the problem.”

“Yeah, are you armed sir?” the trooper said. “Do you have a weapon with you?”

The call came after a flurry of 911 calls by people inside the building, including at least one of the victims, in the minutes after the first shots rang out. The first call came at 7:25 from Steve Hollander, a company executive who, with graze wounds to his jaw and arm, provided an eerie account of the onslaught to the 911 operator as it was continuing. According to the police and 911 tapes, Mr. Thornton appeared to have shot all of his victims, including two who survived, in a matter of minutes.

In the minutes either before or after his call to 911, Mr. Thornton also called his mother, telling her goodbye and, according to relatives who spoke to her, said that he had killed “the five racists” who had been bothering him.

By the time Mr. Thornton called 911, the police and SWAT teams had cordoned off the building and were sweeping it looking for him.

Mr. Thornton told the trooper, William Taylor, that he had two guns, one on him and one somewhere on the warehouse floor.

“I’m not going to kill anybody else, though.”

The trooper told him, “We’re going to have to have you surrender yourself, somehow, here, and not make the situation any worse, you know what I mean.”

“These cops are going to kill me,” Mr. Thornton said, betraying the first hint of fear.

“No, they’re not,” the trooper assured him. “We’re just going to have to get you to relax.”

“I’m relaxed,” Mr. Thornton answered. “I’m calmed down.”

After a few more exchanges, Mr. Thornton — a man with an unremarkable truck driving career and a life’s worth of financial trouble — returned to his complaints with the company.

“Treat me bad,” he said. “I’m the only black driver they got here. Treat me bad all the time.”

“It’s a horrible situation,” the trooper said. “I understand that.”

Mr. Thornton again told the trooper he was calm and indicated he was aware he was creating what may become a public record of his thinking. He said he just wanted “to tell my story, so you can play it back.”

After a few more exchanges, Mr. Thornton for the first time suggested he planned to kill himself. “Where in the building are you, Omar?” the trooper asked.

“I’m not going to tell you that,” he said, later adding, again, “when they find me, everything will be all right.”

The trooper appeared to change course, seeming to make small talk — asking Mr. Thornton what time he arrived at work that morning — but still trying to glean important details, like how many weapons he had and how much ammunition. Mr. Thornton said he had enough to “take care of business.”

Lt. J. Paul Vance, a public information officer for the Connecticut State Police, said Trooper Taylor was a veteran trained for such situations, but he was not specifically directed to speak to Mr. Thornton as a negotiator.

“That was part of his duties that day; he was in charge of the shift and he just happened to pick up,” Lieutenant Vance said. “He was trying to talk him into surrendering, numerous times.”

At one point, Mr. Thornton appeared as if he would turn himself over to the police.

“Well, I guess, I guess, maybe I’ll surrender,” he said. “Nah, they’ll have to come and get me. Let them come and get me.”

Near the call’s end, Mr. Thornton, who never once throughout the call expressed remorse, seemed to become emotional. He asked the trooper to convey his love to his “people.”

“Got to go now,” he said. After a few more efforts to keep him talking, the line went silent.

“Omar?” the trooper said. “Omar? Omar?”

Liz Robbins contributed reporting.

A version of this article appeared in print on August 6, 2010, on page A1 of the New York edition.